Safety switches are used in electrical power distribution systems to electrically isolate a load or a portion of a power circuit.
Purchasers and installers of electrical equipment are increasingly interested in the safety of those using the equipment. Standards have been introduced in an effort to reduce the exposure of individuals to live power over 48 Vac.
Safety switches typically include fuses behind a door. When a fuse clears (opens), the fuse must be replaced. The door of the safety switch must be opened to replace the fuse. The door of the safety switch may be interlocked such that the switch must be in the “OFF” position in order to open the door. However, the line side of the switch may not be disconnected from live voltage. Therefore, the individual replacing the fuse(s) may be exposed to live power which may be over 120 Vac.